All wired up

Nature Neuroscience

December 26, 2011

Physical connections between various parts of the brain can predict neural activity within those regions, finds a study published online this week in Nature Neuroscience. Working out the match between physical connections and activation in the brain is likely to be useful for understanding individual differences in how the brain works, and how the function of the brain changes when these connections change naturally, as when people age. Zeynep Saygin and colleagues focus on the fusiform gyrus, which is important for processing faces. However, as with the rest of the brain, there are many differences from person to person in the exact pattern of neural activity in this region. Using diffusion tractography to work out what brain areas connect to the fusiform gyrus, the authors determine person-specific ‘wiring diagrams’ for this area. Then, they used functional magnetic resonance imaging to track each person’s whole brain activity while viewing faces. By combining the information from these two experiments, Saygin and colleagues find how patterns of physical connectivity match up with the brain activation patterns. In a different group of subjects, the authors were then able to use this information to accurately predict activation patterns in response to faces, just from subjects\\\' individual pattern of physical connections. These results demonstrate that information about the physical connections in the brain can be powerful predictors of how the brain works.